With the development of the mobile communication industry and the growing demand for mobile data services, the demand for the speed and Quality of Service (QoS) of the mobile communications becomes increasingly higher. Based on the above, reasons, the research and development on the next generation mobile communication system, typically a Long-Term Evolution (LTE) project which is initiated by the 3rd Generation Partnership Project (3GPP) and is capable of providing a spectral bandwidth of 20 MHz (megahertz) at most, have already been carried out before the large-scale commercial use of the 3rd-Generation (3G) mobile communications. With the further evolution of the network, the Long-Term Evolution Advance (LTE-A), as an evolved system of the LTE, is capable of providing a spectral bandwidth up to 100 MHz and supporting communications with higher flexibility and higher quality, meanwhile, the LTE-A system has good backward compatibility. The LTE-A system has a plurality of Component Carriers (CCs). One LTE terminal may only operate on a certain backward-compatible CC, while a LTE-A terminal with a higher capacity may transmit on a plurality of CCs the same time. That is, a multi-carrier aggregation technology may be implemented to enable an LTE-A terminal to transmit and receive data in a plurality of component carriers simultaneously, thereby achieving the purpose of increasing the bandwidth.
The LTE-A system supports the multi-carrier aggregation technology to achieve data transmission in a larger bandwidth by multi-carrier aggregation. A base station may manage at most five carriers which are called component carriers and are all backward compatible so as to support operations of a User Equipment (UE) in an early LTE Release. The base station may configure a plurality of component carriers for a UE, and select to activate some or all of the component carriers for the UE, and the activated component carriers can provide data transmission for the UE.
In the research at this stage, the LTE R11 stage has a new requirement in terms of utilization of spectrum resources, energy conservation of networks and interference suppression between cells on the basis of the multi-carrier aggregation technology. For achieving this purpose, New Carrier Type is proposed currently by means of the application of the carrier aggregation technology. The new carrier type has a distinctive feature, that is, more new technologies can be applied therein without considering the backward compatibility in the design. For example, the new carrier in the current LTE R11 is defined that it needs to be applied together with at least one compatible carrier, and the Cell-specific Reference Signals (CRS) of LTE R8 is not configured in the new carrier to avoid severe CRS interference of the neighboring cells at the cell edge, in particular the CRS interference between macro cells and micro cells in a Heterogeneous Network (Het Net) scenario. However, not configuring LTE R8 CRS in the new carrier may result in a problem that there is no reference signals used for synchronization tracking in the new carrier. In discussions on the new carrier type up to now, some companies propose that a Primary Synchronization Signal/Secondary Synchronization Signal (PSS/SSS) is not configured to be sent in some of the new carriers (e.g., synchronous new carriers), the PSS/SSS resources are used to transmit data, and the UE keeps synchronization with the new carrier through a compatible carrier. Some of the new carriers (e.g., asynchronous new carriers) are still configured with the PSS/SSS. A reference signal mainly used for synchronization tracking is introduced into the new carrier, and this reference signal is called Synchronization Track Reference Signal (STRS). The current sending period of the STRS is 5 ms. As to the problem to send the STRS in a full bandwidth or sub-band mode (sending in N Resource Blocks (RB) in the carrier, N is an integer greater than or equal to 6) is still in discussion, and there is no determined mode currently. That is to say, the problem in the related art to use what kinds of modes to send the STRS is still not solved such that the STRS cannot be sent in a new carrier.
Moreover, up to now, introducing the STRS in LTE R11 will still bring large interference between neighboring cells, although compared with the LTE Rel-8 CRS, the interference only occurs in the subframe hearing the STRS (refer to FIG. 1 that shows a structural schematic diagram of radio frames and subframes in the LTE standard according to the related art), the interference is still introduced and will affect the increase of edge efficiency. The interference of the LTE Rel-8 CRS mainly affects the demodulation performance, the STRS is defined here not to be applied in data demodulation, but the interference of the STRS between neighboring cells will still affect the synchronization/synchronization tracking performance. If the later releases define that STRS could be used for demodulation, likewise the interference of the STRS between neighboring cells will affect the demodulation. However, there is no solution in the related an for solving the interference generated by the STRS.
In addition, regarding the transmission of the new carrier, whatever a synchronous new carrier or an asynchronous new carrier, at the base station side, a manner of transmitting the new carrier and the matched compatible carrier simultaneously and synchronously (it is considered to be synchronous within the range of the error defined in Standard Protocols) is adopted currently. However, after the new carrier and the matched compatible carrier are transmitted via the air interface, the different frequency bands of carriers, the ability of bypassing obstacles and the movement speed and directions of the UE will finally result in that the two carriers sent simultaneously at the base station are not synchronous in time and also have different frequency offsets when they arrive at the UE. Hence, when the new carrier is subjected to an initial measurement at the UE side, the UE side does not know whether the new carrier is synchronous with the matched compatible carrier (because they are synchronous at the base station side, but may be not synchronous when they arrive at the UE side), and the UE side does not know whether the UE itself is synchronous with the new carrier, and also does not know whether the PSS/SSS is sent in the to-be-measured new carrier, such that the UE needs to execute several possible processes to detect whether the UE itself is synchronous with the new carrier and to detect whether the PSS/SSS or STRS is configured in the new carrier. Obviously, in the related art, it is aimless to detect the new carrier configuration during the initial measurement for the new carrier at the UE side, which undoubtedly increases the processing complexity of the UE side.
Aiming at the problem that it is aimless to detect the new carrier configuration during the initial measurement for the new carrier at the UE side, there is no effective solving method proposed in the related art.